The present invention relates to a machine for producing granita and similar beverages. The machine is especially designed for coffee granita production. Although here and in the following description reference is made only to an use of the machine for granita production, it should be appreciated that it may be used to contain and dispense other cold drinks.
In granita production machines a sugar-water solution, flavored with an essence, such as coffee or juice of lemon or other fruits, is stirred while it is cooled so that the resulting product is in a slush consistency of minute iced crystals. This is obtained in a bowl being extended in either horizontal or vertical direction, inside which a cooling body is generally in contact with the evaporator of a refrigeration circuit. This refrigeration circuit is contained in a casing of the same granita production machine.
In some of the machines nowadays available on the market, a horizontally elongated bowl, made of transparent material, contains the cooling body in the form of a drum which also is located horizontally on the bottom of the bowl.
The cooling drum houses a coil which is the evaporator of the refrigeration circuit. The crystals of iced solution for producing granita are continuously removed by an auger, which, being arranged concentrically to the cylinder and driven by a geared motor, skims the external side surface of the drum.
The granita machine of the above described kind works in a satisfactory way when the sugar solution in the bowl fills at least half the bowl so that the horizontal cooling drum is abundantly covered. Usually the capacity of a bowl is about 10–12 liters. When the contents in a bowl is less than 5 liters, as the machine incorporates too much air into the water solution during its operation, the obtained product becomes foamy and not more utilizable.